Решите систему, пожалуйста! 90/x-90/y = 5/12 y-x = 20

Система уравнений: 90 / x - 90 / y = 5 / 12 ; y - x = 20 ; 1 ) y - x = 20 ; y = 20 + x ;2 ) 90 / x - 90 / y = 5 / 12 ; 90 / x - 90 / (20 + x ) = 5 / 12 ; ( 90 * ( 20 + x ) - 90 * x) / ( x ^ 2 + 20 * x ) = 5 / 12 ; ( 1800 + 90 * x - 90 * x ) / ( x ^ 2 + 20 * x ) = 5 / 12 ; 1800 / ( x ^ 2 + 20 * x ) = 5 / 12 ; 5 * ( x ^ 2 + 20 * x ) = 12 * 1800 ; ( x ^ 2 + 20 * x ) = 12 * 1800 / 5 ; ( x ^ 2 + 20 * x ) = 4 320 ; x ^ 2 + 20 * x - 4 320 = 0 ; D = b ^ 2 - 4ac = 20 ^ 2 - 4·1·(-4320) = 400 + 17280 = 17680;x1 = ( -20 - √17680 ) / (2·1 ) = -10 - 2√1105 ;x2 = -20 + √17680 2·1 = -10 + 2√1105 ;3 ) y1 = 20 -10 - 2√1105 = 10 - 2√1105 ; y2 = 20 + 10 - 2√1105 = 30 + 2√1105 ;Ответ: ( - 10 - 2√1105 ; 10 - 2√1105 ) и ( -10 + 2√1105 ; 30 + 2√1105 ).